People with spina bifida use their MACE on long-term follow-up: A single institutional retrospective cohort study.

OBJECTIVE: While the Malone antegrade continence enema (MACE) facilitates bowel movements in patients with spina bifida (SB) and neuropathic bowel, little is known about its long-term use. We aimed to assess long-term MACE use and potential risk factors for disuse. METHODS: All patients with SB who underwent MACE procedures at our institution were retrospectively reviewed. Main outcome was MACE disuse (no longer catheterizing the MACE for antegrade enemas) based on self-report on a clinic questionnaire, or medical record for patients last seen before introducing the questionnaire 5 years ago. Survival analysis used two timeframes: time after surgery (Analysis 1) and chronological age: accounting for older children reaching adulthood earlier (Analysis 2). RESULTS: Overall, 411 patients (54% female, 78% shunted, 65% augmented) underwent a MACE procedure at median 7.9 years old (median follow-up: 8.4 years). Thirty-three (8%) patients no longer used their MACE. Most common reasons for doing so were channel/stomal stenosis (61%) and excision at colostomy or other abdominal surgery (12%). Bowel management afterwards included oral agents ± enemas (55%), Chait tube (30%), colostomy (12%). After correcting for differential follow-up, 90% of participants used their MACE at 10 years and 87% at 15 years after surgery. Based on chronological age, 97% used their MACE at 15 years old, 92% at 20 and 81% at 30 (Summary Figure). On multivariate analysis, umbilical MACEs were 2.4 times more likely to be disused than right lower quadrant MACEs (p = 0.04). Without correcting for chronological age (Analysis 1), patients undergoing MACE surgery at older ages were more likely to stop MACE use (p = 0.03). However, after accounting for chronological age (Analysis 2), patients undergoing a MACE procedure at older ages were no more likely to stop its use (p = 0.47, Figure). Gender, SB type, shunt status, mobility status, bladder augmentation or a urinary catheterizable channel were not associated with stopping MACE use (p ≥ 0.10). COMMENT: Participants were regularly followed in multi-disciplinary SB clinics. We did not assess continence, satisfaction or long-term urinary channel use, making it premature to recommend optimal stomal locations. CONCLUSIONS: Most patients with SB followed by a multi-disciplinary team continue using their MACE; 1% stopped MACE use annually, particularly after adolescence. This strongly suggests it is an effective bowel management method and transitioning to self-care plays a role in maintaining long-term MACE use. Umbilical MACEs may be at high risk of disuse, but all people with a MACE can benefit from support as they transition to adult care.

Estimating and tracking renal function in children and adults with spina bifida.

PURPOSE: Estimated glomerular filtration rate (eGFR) in the general population is stable in children after 2 years of age until adulthood. In the first three decades after age 18, eGFR decreases by 0.3-0.8 ml/min/1.73 m2/year. Little data exists regarding eGFR changes in the spina bifida (SB) population given variability in muscle mass. In the absence of a validated SB-specific eGFR formula, the performance of different eGFR formulas may vary. We performed a cross-sectional study (1) to determine trends in eGFR with increasing age in children and adults with SB and (2) to compare eGFRs calculated using different formulas. METHODS: We retrospectively reviewed records of patients 2-50 years old with SB followed at our institution (2014-2019). We determined eGFR using four pediatric formulas (2-17 years: CKiDSCr, CKiDCys, CKiDSCr-Cys, ZappitelliSCr-Cys) and four adult formulas (18 + years: MDRDSCr, CKD-EPISCr, CKD-EPICys, CKD-EPISCr-Cys). One eGFR per patient was included (most recent eGFR for those with serial measurements). Patients were categorized as chronic kidney disease (CKD) stage 2 (eGFR 60-89) and Stage 3+ (<60). Non-parametric tests, linear regression, and Spearman's correlation were used for analysis. RESULTS: Among 209 children with SB (median age 10.3 years), depending on the formula used, eGFR decreased by -0.7 to -1.8 ml/min/1.73 m2/year (CKiDCys, CKiDScr, p ≤ 0.001), remained stable (CKiDSCr-Cys, p = 0.41), or increased by +2.7/year (ZappitelliSCr-Cys, p < 0.001) (Figure). The proportion of children with CKD 2 or higher varied between formulas (11.5-58.9%, p < 0.001). Correlations between pediatric formulas were negligible to moderate. Comparing any two formulas, 12.0-65.6% of children were assigned a different CKD stage. Among 164 adults (median age 26.3), eGFR decreased for each formula (range: -1.3 to -2.2/year, p ≤ 0.01) (Figure). The proportion of adults with CKD 2 or higher varied between formulas (9.2-30.5%, p < 0.001). Correlations between adult formulas were moderate to very high. Comparing any two formulas, 8.5-26.8% of adults were assigned a different CKD stage. COMMENT: We cannot reliably determine whether eGFR changed during childhood. Among adults, eGFR decreased with age for every formula evaluated at greater than twice the general population rate. Without a validated SB-specific eGFR formula, we are left with formulas providing different results. CONCLUSIONS: Estimated GFR among adults with SB appears to deteriorate at a higher rate than in the general population. Due to lack of precision of accepted eGFR formulas in the SB population, this may be a real phenomenon, an artifact of inaccurate eGFR formulas, or both. A validated SB-specific eGFR formula is needed.